Safety device



Sept. 8, 1942.

A. .J. WVIEDINGERV SAFETY navrcm I Filed May l6 1940 Patented Sept. 8,1942 i UNITED STATES PATENT OFFICE 2,295,441 SAFETY DEVICE Arthur J.Wiedinger, Akron, Ohio, assignor to' Wingfoot Corporation, Wilmington,Del., a corporation of Delaware Application May. 16, 1910, Serial. No.335,533

10 Claims.

The present invention relates to. safety devices to be used on machinesin which there are exposed moving parts, and the principal object ofthis invention is to devise a safety device to stop the operation of themachine or to so minimize the dangerous character thereof as to renderit harmless to the operator.

Another object of this invention is to provide a safety device of thischaracter, in which an operator in the face of an impending accidentmay, without a great amount of mental consideration, operate the safetydevice to stop the machine, or otherwise render it harmless.

Other objects of this invention will appear hereinafter as thedescription hereof proceeds, the novel features, arrangements andcombinations being clearly set forth in the specification and claimsthereunto appended.

In the drawing the single figure represents a perspective view of mysafety device as applied to a rubber mill.

My safety device is illustrated as applied to a rubber mill, but it isto be understood that the invention is not limited solely to machines ofthis character as its utility will be apparent for other types ofmachines in which there is an ever-present danger to the worker.

In the drawing, Ill indicates the end frames of a mill provided with theusual rolls II and I2 driven by the gears I3 and I4, respectively, whichin turn are driven by a motor H) or other power-operated means throughthe intermediacy of the gear it. The motor is connected to a source ofpower through the usual power line ll, in which there is arranged aswitch l8 to interrupt the flow of current to the motor if and when anemergency exists and it becomesimperative to stop the machine. In caseof an emergency the switch is adapted to be thrown to the off positionby my safety device when the safety device is operated and, if desired,in addition to stopping the operation of the motor, mechanism may bebrought into play to separate the rolls II and i2.

Mounted on the end frames [0 of the mill are the standards l9, to theupper ends of which are secured, as by welding, the eyes 20. Alsomounted on the standards are the pulleys 2| freely mounted at 22 forpivotal or swiveling action.

The main safety cables or control members at the front and back of themachine are indicated by the reference numeral 23. These cables have oneend thereof secured, as at 24, to brackets 20 at the left and arethreaded through the eyes 20 at the right as clearly illustrated in thedrawing, the two cables being clamped together as at 25 by any suitableclamp or fastening device. One of the cables 23 is connected to theoperating lever 26 of the switch 18, and it will be apparent that a pullexerted on either of the cables 23 will operate the lever 26 of theswitch l8 and throw it to the off position.

Suspended from each of the cables 23 intermediate the brackets 20 is alongitudinal rod 21 arranged substantially parallel to the cable 23 andsuspended therefrom by the vertical cords 28. The vertical cords are inturn connected transversely by means of the cords 29. With thisarrangement it will be noted that the bar 21 is supported by a networkof cords which covers an appreciable area close to the operatorsposition so that in case of an impending accident the operator may reachout and clutch at, the network of cords and exert a pull on the networksufficient to pull the cable 23 and throw the switch l8 to the offposition. An operator might easily miss grabbing a single cable locatedat a definite position even though he had an appreciation ofapproximately where that cable was located, but, in view of theextensiveness of the network embodied in this invention, the operatormerely has to reach out in the general vicinity of the cable and as soonas his hand contacts the network he can grab and pull to stop theoperation of the machine. In an emergency seconds may mean thedifference between life or death, or at least it may mean the differencebetween being crippled for life and avoiding injury.

The weight of bar 21 at the bottom of the network tends to hold thenetwork in a substantially fixed vertical plane and to hold the samemore-or-less taut at all times, which greatly facilitates the operationof the network as the cords are tensioned at all times and will nottherefore have a tendency to move away from the operators hand when heclutches at the network. It is desirable however that the lower part ofthe network can swing, so that if accidentally hit by a lateral blow itwill not tend to operate cord 23 and stop the machine. Also, some timesin the operation of mills of this character, the rubber, after beingrolled up on one roll by the operator, may strike the lower part of theguard when released by the operator to be fed into the bite of therolls, and it is not desirable that the safety device be operated underthese conditions. A mere upward or lateral push on the rod 21 will notnormally operate the safety device and, since the lower part of thenetwork is apt to be struck by the operator or by the material he isworking with, it is very desirable that the network be free to move outof position to some extent without stopping the machine if struck fromthe side or from below.

The bar 21 is kept from swinging and is steadied by the weights 3!!suspended by cords 3| trained over the pulleys 2| and secured to theends of the bar. In order to tension the cables 23 springs 32 areemployed. These are connected at one of their ends to the cables 23 andat their other ends to the standards I9. Thus, normally the weight ofthe network and bar does not tend to pull the switch [8 to the.ofi-position since the weight is taken 01'1" the cords intermediate thesprings and the switch. The springs, however, are approximately onlysufficient to balance the weight of the network and connected mechanismsand, when the operator pulls on the network to operate the cord 23,these springs will readily yield to the extra load and permit theoperation of the switch in the manner aforesaid.

Summarizing the essence of the safety device, it will be apparent thatther is provided a network of cords hanging more-or-less freely from thecord which operates the control switch. This network is preferablyweighted at its lower end by the bar 21 and the bar is kept fromswinging under ordinary conditions by means of the weights 30. However,when occasionrequires, the mere grasping of the network at any part ofits area, together with a pull on same will cause the operation of theswitch I8 to the off position, with the result that the motor isstopped.

The rolls may or may not be connected to the safety device and be movedapart, depending upon the particular system that is to be employed.

Note that the two networks guard opposite sides of the apparatus toprotect the operator while working at either side.

In a mill of this character there is the everpresent danger that throughsome slip the operator may be dragged into the bite between the rollswith naturally disasterous results. The device also has utility in casethere is impending destruction of the roll as, for instance, where a newoperator might find a large piece of foreign material that is going downbetween the bite of the rolls. In this case he can reach out and quicklyoperate the safety device to stop the mill While foreign material isremoved therefrom.

In certain types of mills the rubber stock is carried directly off themill in a narrow strip upwardly to an overhead conveyor or to another rfloor of the building where it is to be used. Some times this stripbreaks and the end of the strip snaps with a whipping action. If themill is provided with an ordinary safety cable, a slight amount ofcontact between the end of this strip and the safety cable will operatethe safety cable and not only stop the machine on which it is mounted,but will also stop a whole series of machines, since generally there isa tie-in between all of the mills on the safety feature so that anoperator at any machine in the series may shut off all of the machinesin the series, as it frequently happens that the operator of the machineat which there is an impending disaster may not be in a position tooperate the cable himself, and by the time any one else reached the millit might be too late.

With the present invention, however, the strip of material, if itbreaks, will hit the lower bar of the safety device and this of coursewill not operate the safety cable. The practical result of thisarrangement is that all of the mills in the series are kept runningcontinuously, except when it is absolutely necessary to shut them downbecause of some impending disaster or accident. It is not a very easything to start the series of machines again after they have once beenshut down becaus the mechanism is usually so arranged that the rolls, inaddition to being stopped, are simultaneously moved into a greaterspaced relation with respect to each other and considerable time isconsumed in again getting all of the mills to function properly. Forthis reason the ordinary safety cable is not sufficient.

My improved device prevents undesired operation of thesafety cable,while at the same time greatly facilitates the operation thereof when itis necessary to do so.

Obviously those skilled in the art to which this invention pertains maymake various changes in the particular arrangement and construction ofthe parts shown therein without departing from the spirit of thisinvention, and therefore I do not wish to be limited except as may behereinafter set forth in the claims.

Having thus fully described my invention, what I claim and desire tosecure by Letters Patent of the United States is:

1. In combination with a machine having exposed moving partsrepresenting a hazard to an operator working on said machine, of powermeans for driving said machine, a control member or the like extending asubstantial distance across the operators side of the machine, a networkof cords or the like suspended from said control member adjacent theoperators position at said machine, actuating means operable to rendersaid power means ineffectual to drive said machine, and aconnectionbetween said control member and said actuating means foroperating said actuating means when said control member is either pulledor actuated by pulling on any part of said network.

.2. In combination with a machine having exposed moving partsrepresenting a hazard to an operator working on said machine, of powermeans for driving said machine, a cable or the like extending asubstantial distance across the operators side of the machine, a networkof cords or the like suspended from said cable adjacent the operatorsposition at said machine, actuating means operable to render said powermeans ineffectual to drive said machine, and a connection between saidcable and said actuating means for operating said actuating means whensaid cable is either pulled or actuated by pulling on any part of saidnetwork.

3. In combination with a machine having exposed moving partsrepresenting a hazard to an operator working on said machine, of powermeans for driving said machine, a control member or the like extending asubstantial distance across the operators side of the machine, a networkof cords or the like freely suspended from said control member adjacentthe operators position at said machine, a bar attached to said networkand suspended thereby for keeping said network normally in asubstantially vertical plane, actuating means operable to render saidpower means ineffectual to drive said machine, and a connection betweensaid control member and said actuating means for operating saidactuating means when said control member is of said network or bar.

4. In combination with a machine having exposed moving partsrepresenting a hazard to an operator working on said machine, of powermeans for driving said machine, a control member or the like extending asubstantial distance across the operators side of the machine, a networkof cords or the like suspended from said control member adjacent theoperators position at said machine, a bar attached to said network andsuspended thereby for keeping said network normally in a substantiallyvertical plane, yielding means connected to said bar to permitrestrained swinging movement thereof, actuating means operable to rendersaid power means inefiectual to drive said machine and a connectionbetween said control member and said actuating means for operating saidactuating means when said control member is either pulled or actuated bypulling on any part of said network or bar.

5. A safety device for rendering inoperative the power-operating meansfor driving a machine comprising means adapted to be connected to thepower-operated means for said machine for rendering it inoperative, aflexible supporting element, and a network of flexible, substantiallyinextensible members carried by the element and adapted to be arrangedin a convenient position to be reached by the operator while working atsaid machine, said element being connected to said means to actuate thesame when a pull is exerted on substantially any part of said network.

6. A safety device for rendering inoperative the power-operating meansfor driving a machine comprising means adapted to be connected to thepower-operated means for said machine for rendering it inoperative, anetwork of flexible, substantially inextensible members adapted to bearranged in a convenient position to be reached by the operator whileworking at said machine, and connected to said means to actuate the samewhen a pull is exerted on substantially any part of said network, andmeans weighting the lower edge of said network to stabilize the positionof said network.

7. A safety device for shutting off the power to a power-operatedmachine, comprising a substantially horizontally disposed flexibleelement adapted to be connected to the said power means and arrangedwithin easy reach of the operator for rendering said power meansineffective to drive said machine, and a plurality of flexible elementssubstantially parallel to said first element and suspended therefrom,whereby a pull exerted on any of said elements will actuate said firstelement to render said power means inoperative.

8. A safety device for shutting off the power to a power-operatedmachine, comprising a substantially horizontally disposed flexibleelement adapted to be connected to the said power means and arrangedwithin easy reach of the operator for rendering said power meansineffective to drive said machine, yielding means for holding saidflexible element in an inoperative position, and a plurality of flexibleelements parallel to said first element and suspended therefrom, wherebya pull exerted on any of said elements will actuate said first elementto render said power means ineffective.

9. A safety device for shutting off the power to a power-operatedmachine, comprising a substantially horizontally disposed flexibleelement adapted to be connected to the said power means and arrangedwithin easy reach of the operator for rendering said power meansinefiective to drive said machine, yielding means for holding saidflexible element in inoperative position, a plurality of flexibleelements parallel to said first element and suspended therefrom, wherebya pull exerted on any of said elements will actuate said first elementto render said power means ineffective, and 'means for yieldinglyresisting swinging movement of said flexible elements.

10. In combination with a machine having exposed moving parts at atleast two different operators positions and representing a hazard to anoperator working on said machine, of power means for driving saidmachine, separate control members or the like extending for asubstantial distance adjacent each of the operators positions, a networkof cords or the like suspended from each control member, actuating meansoperable to render said power means ineffectual to drive said machineand a common connection between each of said control members and saidactuating means for operating said actuating means when either of saidcontrol members is either pulled or actuated by pulling on any part ofeither network.

ARTHUR J WIEDINGER.

